package edu.csl.study.springcloud.common.intercepter;

import feign.RequestInterceptor;
import feign.RequestTemplate;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpServletRequest;
import java.util.Enumeration;

/**
 *  Feign传递上下文
 *  @author zhudeming
 */
public class FeignUserContextInterceptor implements RequestInterceptor {

	@Override
	public void apply(RequestTemplate template) {
		ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder
                .getRequestAttributes();
		if(attributes == null){
		    return;
        }
		HttpServletRequest request = attributes.getRequest();
        Enumeration<String> headerNames = request.getHeaderNames();
        if (headerNames != null) {
            while (headerNames.hasMoreElements()) {
                String name = headerNames.nextElement();
                String values = request.getHeader(name);
                template.header(name, values);
            }
        }

	}

}
